Zero Turning Radius Lane Maintenance Machine

ABSTRACT

A bowling lane maintenance machine, after completing a maintenance operation on one lane, moves onto the approach behind the foul line, turns and indexes over to the next lane, then turns again and moves up to the foul line of the next lane. Preferably, the machine is self-indexing so that all operations are carried out without operator intervention. Left and right wheels that drive the machine on the approach can be driven at relatively different speeds and in opposite directions to enable the machine to turn about a zero radius.

RELATED APPLICATIONS

This application claims the priority benefit of provisional patent application No. 60/865,306 filed Nov. 10, 2006, said provisional application being hereby incorporated by reference into the present specification.

TECHNICAL FIELD

The present invention relates to the field of bowling lane maintenance machines; more particularly, to the way such machines are controlled during travel up and down the lane and on the approach during movement from lane-to-lane.

BACKGROUND AND SUMMARY

Typical prior art lane maintenance machines must be manually moved from one lane to the next after the machine has completed its maintenance operation on the lane. An exception is found in prior U.S. Pat. No. 5,185,901, assigned to the assignee of the present invention, wherein the machine automatically indexes from lane-to-lane without operator intervention. The present invention provides a number of improvements to the concepts disclosed in the '901 patent, particularly with respect to the manner in which the machine maneuvers on the approach as it travels between lanes. Although in its most preferred form the machine of the present invention is totally self-indexing from one lane to the next, some aspects of the invention are not necessarily limited to self-indexing.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a left front perspective view of a non-zero turning radius maintenance machine embodying the principles of the present invention with its top cover removed to reveal internal details of construction;

FIG. 2 is a right rear perspective view of the machine;

FIG. 3 is a right front perspective illustration of certain internal components of the machine with walls and other structures removed for clarity;

FIG. 4 is a left rear perspective illustration of certain internal components of the machine with walls and other structures removed for clarity;

FIG. 5 is a right side elevational view of the machine with the near sidewall thereof removed to reveal internal details of construction;

FIG. 6 is an enlarged, fragmentary right side elevational view of the machine illustrating the action of the squeegee blades as they engage the lane during forward travel of the machine;

FIG. 7 is an enlarged, fragmentary right side elevational view of the machine similar to FIG. 6 but illustrating the machine stopped at the end of its forward travel with the squeegee assembly passed beyond and overhanging the edge of the pin deck to flip moisture off the squeegee assembly;

FIG. 8 is an enlarged, fragmentary right side elevational view of the machine similar to FIG. 6 but illustrating the squeegee assembly in a raised position;

FIGS. 9-13 are block diagrams of the different portions of the electrical system of the machine;

FIG. 14 is a left front perspective view of a zero turning radius maintenance machine embodying the principles of the present invention with its top cover removed to reveal internal details of construction;

FIG. 15 is a right rear perspective view of the machine of FIG. 14;

FIG. 16 is a right front perspective illustration of the zero turning radius machine with walls and certain other components removed to reveal internal details;

FIG. 17 is a left rear perspective illustration of the zero turning radius machine with walls and certain other components removed to reveal internal details;

FIG. 18 is a right rear bottom perspective illustration of the zero turning radius machine with walls and certain other components removed to reveal internal details;

FIG. 19 is a left rear bottom perspective illustration of the zero turning radius machine with walls and certain other components removed to reveal internal details;

FIG. 20 is an enlarged right rear top perspective illustration of the zero turning radius machine with walls and certain other components removed to reveal internal details;

FIG. 21 is a left side elevational view of the zero turning radius machine illustrating the manner in which it tips forward by gravity on the approach so as to be supported by zero turning radius drive wheels and castor wheels;

FIG. 22 is an enlarged, fragmentary, left front perspective view of the zero turning radius machine with portions of the front bumper plate broken away to reveal details of construction therebehind;

FIG. 23 is an enlarged, fragmentary perspective view of the left front corner of the zero turning radius machine with the front bumper plate removed to reveal details of the seven pin whisker assembly;

FIG. 24 is a fragmentary vertical cross-sectional view of the seven pin whisker assembly taken substantially along line 24-24 of FIG. 23; and

FIGS. 25-29 are block diagrams of the different portions of the electrical system of the zero turning radius machine.

DETAILED DESCRIPTION Non-Zero Turning Radius Machine

The present invention is susceptible of embodiment in many different forms. While the drawings illustrate and the specification describes certain preferred embodiments of the invention, it is to be understood that such disclosure is by way of example only. There is no intent to limit the principles of the present invention to the particular disclosed embodiments.

The machine 10 illustrated in the drawings is similar in many respects to the machine disclosed in U.S. Pat. No. 5,729,855 and U.S. Pat. No. 6,939,404. Accordingly, the '855 and '404 patents are hereby incorporated by reference into the present specification. In view of the full disclosure in the '855 and '404 patents of the construction and operation of the lane machine, the construction and operation of the machine 10 will be described only generally herein.

The machine 10 has a cleaning system denoted broadly by the numeral 12 and located generally in the front of the machine. A dressing (preferably oil) application system is denoted broadly by the numeral 14 and located generally in the rear portion of the machine. These two systems perform their functions as the machine is propelled down the lane and back by lane-engaging drive wheels 16 and 18 fixed to a transverse shaft 20 that is powered by a drive motor 22 (Baldor 24 VDC model 24A531Z019G1) and a chain and sprocket assembly 24. A conventional proximity sensor speed tachometer 25 (FIG. 9) is coupled with the end of drive shaft 20.

The oil application system 14 includes an applicator roll 26 (hereinafter sometimes referred to as the “buffer”) disposed for engaging the lane surface, a reciprocating oil dispensing head 28 that travels back and forth across the width of the lane above buffer 26, and abrush assembly 30 between buffer 26 and dispensing head 28 for receiving oil from head 28 and delivering it to buffer 26. Buffer 26 is rotatably driven by a buffer motor 31 (Baldor 24 VDC model 24A532Z046G1) (FIG. 10). Buffer 26 pivots up and down, in and out of contact with the bowling lane surface by way of linkage 27 operated by a buffer up/down motor 29 (Merkle Korff 31 RPM 24 VDC model S-3727-87D) (FIG. 12). In the down position, buffer 26 operates a buffer down limit switch 21 and operates a buffer up limit switch 23 in the up position.

Details of the construction and manner of use of brush assembly 30 are disclosed in U.S. Pat. No. 7,056,384 titled “Strip Brush Bowling Lane Dressing Application Mechanism”, which is hereby incorporated by reference herein. Oil application system 14 additionally includes a reservoir 32, a positive displacement pump (not shown) (FMJ model RHOCKC Lab Pump Jr.) having a motor 33 (FIG. 10) (Dayton 24 VDC model3XE19) for supplying oil from reservoir 32 to dispensing head 28, and a three-way valve 35 (FIG. 9) for controlling the flow of oil. In a recycle position valve 35 recycles oil back to reservoir 32, and in a delivery position valve 35 delivers oil from pump 33 to dispensing head 28.

Oil dispensing head 28 is mounted for reciprocation along a transverse guide track 34 extending between the sidewalls of the machine. An endless drive belt 36 is secured to head 28 and has its opposite ends looped around a pair of pulleys 38 and 40, the pulley 40 being operably coupled with a reversible motor 42 (Crouzet 24 VDC model 808050Y07.66Z) to provide driving power to belt 36 and thus propel dispensing head 28 along track 34. A pair of left and right sensors in the form of proximity switches 44 and 46 adjacent opposite ends of the path of reciprocal travel of dispensing head 28 are operable to sense the presence of dispensing head 28 as it reaches the limits of its path of travel so as to signal the motor 42 to reverse directions and drive dispensing head 28 in the opposite direction along track 34.

The pulley 38 is fixed to a long fore-and-aft extending shaft 48 disposed just outboard of the right sidewall of the machine. Near its rear end, just forwardly of pulley 38, shaft 48 is provided with a notched wheel 50 whose rotation is sensed by a sensor 52. An output from sensor 52 is sent to the control system of the machine (described in more detail below) for the purpose of determining the precise location of the oil dispensing head 28 across the width of the machine and the bowling lane. Such location is coordinated with a particular lane oil pattern that has been programmed into the control system of the machine so that oil dispensing head 28 may be actuated to precisely dispense oil at predetermined locations along its path of reciprocation.

Distance down the lane is determined by a pair of lane-engaging wheels 53 (FIGS. 3, 4 and 5) located just in front of the rear wall of the machine. Wheels 53 are fixed to a common cross shaft 54 that rotates a notched wheel 55 (FIG. 4) via a chain drive 56 (FIG. 3). The number of revolutions of notched wheel 55 is detected by a sensor 57 (FIG. 4) that sends a signal to the control system of the machine.

The cleaning system 12 includes one or more cleaning liquid dispensing heads 58 that reciprocate across the path of travel of the machine as it moves along the lane. While system 12 may also include one or more pressurized spray nozzles as in conventional machines, in a preferred embodiment no such conventional spray nozzles are utilized. In the particular embodiment disclosed herein, only a single dispensing head 58 is utilized, such head 58 traveling essentially the full transverse width of the machine to the same extent as the oil dispensing head 28.

Dispensing head 58 includes a vertically disposed, depending discharge tube 60 provided with a tip 62 that is located close to the lane surface. In one form of the invention, tip 62 is not in the nature of an atomizing nozzle but is instead configured and arranged to emit liquid in a fairly coherent stream so that a bead of cleaning liquid is laid down on the lane surface. One suitable tip 62 for carrying out this particular non-atomizing function is available from the Value Plastics Company of Fort Collins, Colo. as part number VPS5401001N. Other types of tips (not shown) that atomize, breakup or diffuse liquid supplied to the tip may also be utilized where broader surface area coverage by the cleaning liquid is desired. In either case, tip 62 is preferably provided with an internal check valve (not shown).

Cleaning system 12 further includes a guide track 64 attached to the front wall of machine 10 that slidably supports dispensing head 58 for its reciprocal movement. Track 64 extends across substantially the entire width of machine 10 to the same extent as the track 34 associated with oil dispensing head 28. An endless drive belt 66 is attached to dispensing head 58 for providing reciprocal drive thereto, the belt 66 at its opposite ends being looped around a pair of pulley wheels 68 and 70 respectively.

Although pulley 68 maybe driven in a number of different ways, including by its own separate drive motor, in a preferred form of the invention pulley 68 is fixed to the forward most end of shaft 48 from pulley 38 so that both dispensing heads 28 and 58 are driven by the same reversible motor 42. Consequently, both oil dispensing head 28 and cleaning liquid dispensing head 58 are reciprocated simultaneously by motor 42 when the latter is actuated. However, it will be noted that oil dispensing head 28 and cleaning liquid dispensing head 58 reciprocate in mutually opposite directions due to the fact that oil dispensing head 28 is secured to the upper run 36 a of its drive belt 36 while cleaning liquid dispensing head 58 is secured to the lower run 66 b of its drive belt 66.

Cleaning system 12 further includes a cleaning solution reservoir 72 at the rear of machine 10. A supply line 74 leading from reservoir 72 is coupled in flow communication with a reversible peristaltic pump 76 (Barnant 24 VDC model D-3138-0009). An outlet line 80 from pump 76 leads to discharge tube 60 of dispensing head 58 for supplying cleaning liquid to head 58. A cleaner control 82 (FIGS. 10 and 11) is electrically connected to cleaner pump 76 for adjusting the speed of pump 76, and thus the amount of cleaner discharged by head 58.

Because pump 76 is preferably a peristaltic pump, it supplies liquid to dispensing head 58 in constant volume slugs or squirts that enable the cleaning liquid to be very precisely and accurately metered onto the lane surface. Furthermore, it permits the supply of liquid to dispensing head 58 to be essentially instantaneously stopped and started, which, in conjunction with control valve 82, affords precise, board-by-board control over the pattern of cleaning liquid applied to the lane surface by dispensing head 58.

Cleaning system 12 additionally includes a wiping assembly 88 immediately behind cleaning liquid dispensing head 58. Assembly 88 includes a web 90 of soft material such as duster cloth looped around a lower compressible back-up member 92 in the nature of a roller that extends across the full width of the machine. Cloth 90 is stored on a roll 94 and is paid out at intervals selected by the operator and taken up by a takeup roll 96. Wiping assembly 88 is similar in principle to the corresponding wiping assembly disclosed in U.S. Pat. No. 6,615,434, which patent is hereby incorporated by reference into the present specification. A duster unwind motor 95 (FIG. 12) (Merkle Korff9 RPM 24 VDC S-3828-87D) is coupled with roll 94 and, when activated, rotates roll 94 to let out slack in the cloth, allowing backup member 92 to gravity to the lane surface. A duster windup motor 97 (FIG. 12) (Merkle Korff9 RPM 24 VDC S-3828-87D) is coupled with takeup roll 96 and, when activated, rotates roll 96 to raise backup member 92 off the lane surface.

A further component of cleaning system 12 comprises a vacuum pickup head 98 located behind wiping assembly 88. Vacuum pickup head 98 extends essentially the full width of machine 10 and includes a squeegee assembly 99 comprising a pair of resilient, squeegee-type blades 100 and 102 that assist in picking up the thin film of cleaning liquid left on the lane surface after the wiping assembly 88 has acted upon the liquid. Lift linkage 101 is connected to a squeegee lift motor 103 (FIG. 12) (Merkle Korff31 RPM 24 VDC S-3727-87D) and is operably coupled with suction head 98 and squeegee assembly 99 for moving the same between an operating position in engagement with the lane as shown in FIGS. 5, 6 and 7 and a raised position out of engagement with the lane as shown in FIG. 8. A large vacuum hose 104 leads from pickup head 98 to a holding tank 106 for storing liquid picked up by head 98. Vacuum pressure within holding tank 106 is obtained by means of a vacuum motor 107 (Ametek 24 VDC model 116155-00) (FIG. 10) coupled with tank 106.

FIGS. 9-12 are block diagrams illustrating various portions of the control system 108 of machine 10. Control system 108 includes, in addition to the electrical components already mentioned above, controller 110 (programmable logic controller Omron model CPM2A), drive motor control 112, printed circuit board 114, and control relays CR1, CR2, CR3, CR4, CR5, CR6, CR7, CR8, CR9, CR10, CR11, and CR12. Control system 108 further includes start switch 116 (FIG. 9) and an emergency stop switch 117 (FIG. 13).

An electrical power supply system 120 for machine 10 is illustrated in FIG. 13, portions of system 120 also being visible in FIGS. 1-12. In a preferred embodiment of the invention, the heart of power system 120 comprises a pair of series-connected, 12 VDC rechargeable storage batteries 122 (EnerSys Energy Products model Odyessey PC925) that jointly provide up to 24 volts DC power to operating components of the machine. Batteries 122 are connected to a forty amp charger 124 (Iota charger model DLS-27-40 with IQ Smart Charge Controller) that, in turn, is connected to a receptacle 126 (FIG. 1) on the left sidewall of the machine. Receptacle 126 may be connected to a 120 VAC outlet in the bowling center using an electrical supply cord (not shown) in order to recharge batteries 122 from time-to-time, or to run the machine on 120 VAC power supply. As is well understood by those skilled in the art, charger 124 converts 120 VAC power from the supply cord to 24 VDC power for recharging batteries 122 and/or for operating the 24 VDC operating and control components of the machine. Preferably, a constant voltage regulator 128 (Solar Converters Inc. model CVP 12/24-15) is interposed between batteries 122 on the one hand and dispensing head motor 42, oil pump motor 33, buffer motor3 1, three-way valve 35, and drive motor 22 on the other hand to maintain constant voltage to such components.

Operation

The operation of machine 10 is controlled by way of the programed operating controller 110. Although machine 10 may be selectively operated through appropriate switches to clean the lanes only, or to oil the lanes only, in the following example machine 10 is operated to both clean and oil the lanes.

Initially machine 10 is placed on the approach of a bowling lane just behind the foul line. The operator presses start switch 116 one time, which initiates the sequence of maintenance operations. A variety of lane oil patterns can be selected by way of the key pad and display 130 (FIG. 1) as is conventional. The duster unwind motor 95 comes on at this time to dispense a new section of cloth, but if the normally open contacts of duster up switch 134 do not open up, there will be a “duster empty” error displayed. The squeegee assembly 99 will move down and stop when the normally open contacts of down switch 132 close. If the switch contacts do not close, there will be a “squeegee did not lower” error displayed. The oil pump 33 also turns on.

The machine 10 is then pushed onto the lane and properly seated. The start switch 116 is pressed a second time and the dispensing heads motor 42 will start up and cause both heads 28 and 58 to begin moving. Oil dispensing head 28 moves from left to right, as the lane is viewed from the foul line looking toward the pin deck, while cleaner head 58 moves from right to left.

Cleaner pump motor 76 is energized at the same time as heads motor 42. Thus, as cleaner head 58 starts to move, it also starts to apply cleaner instantly to the lane and does not stop until the last programmed “squirt distance” down the lane has been reached. When the oil head 28 reaches the right board edge proximity switch 46, the moving heads 28, 58 will reverse their directions and oil head 28 will begin to apply the first stream of oil.

The oiling head 28 is now moving in a right-to-left direction, while cleaner head 58 is moving in a left-to-right direction. When oiling head 28 reaches the left board edge proximity switch 44, the heads motor 42 will reverse, at which time buffer motor 31 starts up and drive motor 22 is energized to start the machine moving down the lane. Vacuum motor 107 has remained in an “off” condition during this initial startup phase, but after machine 10 has traveled about two feet down the lane, vacuum motor 107 turns on. It is also to be noted that after start switch 116 has been pressed a second time, machine 10 will start a clock (not shown) to record the total amount of run time on the display 130. The total amount of time the three-way valve 35 dispenses oil for each lane is also shown in the display 130.

As machine 10 travels forward down the lane, the oiling and cleaning heads 28, 58 continue to operate, applying oil and cleaner. The board-counting sensor 52 monitors the positions of the moving heads 28, 58. If the motion is interrupted, an error message will be displayed.

During movement of the machine 10 down the lane, the lane distance sensor 57 counts inches traveled and monitors movement of the machine. If travel is interrupted, an error message will be displayed. The speed of machine 10 is also being monitored by the speed tack 25 and is displayed continuously. As the machine continues to move forward, speeds will change (through a drive motor speed control (KB model KBBC-24)) and oil and cleaner will continue to be dispensed to the lane as programmed. As the machine approaches the applied oil distance in accordance with the selected program, the oil pump motor 33 turns off but the buffer motor 31 stays on so buffer 26 continues to buff oil onto the lane.

When the oil distance is reached, buffer 26 stops and buffer lift motor 29 is energized to raise buffer 26 off the lane until buffer up limit switch 23 is operated. If the contacts for raising buffer 26 do not close, there will be an error message displayed. If the up switch 23 sticks closed when it should be open, a “brush down” error message will be displayed.

Additionally, when the oil distance has been reached machine 10 will shift into high speed and continue to travel toward the pin deck. As the machine approaches the pin deck, the programmed distance for the application of cleaner will be reached, causing cleaner pump motor 76 to be turned off and heads motor 42 to be deenergized so as to stop movement of dispensing heads 28, 58. At the same time the machine will down-shift to low speed to reduce its momentum into the pin deck.

When machine 10 enters the pin deck, the duster windup motor 97 will turn on and start to windup the cloth to raise the backup member 92. The normally open contacts of the duster up switch 134 will close to turn off the duster windup motor 97. If the contacts do not close, there will be a “duster did not wind up” error message displayed.

Machine 10 then continues the rest of its travel with squeegee assembly 99 engaging the lane in the manner illustrated in FIG. 6 before coming to a stop at a point where the front of the machine, including squeegee assembly 99, travels off and overhangs the edge 136 of the pin deck 138 as illustrated in FIG. 7. Drive motor 50 has been shut off. This allows the resilient blades 100, 102 of squeegee assembly 99, which have been flexed rearwardly as the machine travels forwardly down the lane, to flip resiliently forwardly in a quick snapping action and throw off cleaning liquid moisture that may otherwise cling to the blades. Squeegee lift motor 103 is then activated to lift squeegee assembly 99 and suction head 98 into a raised position as illustrated in FIG. 8. Squeegee lift motor 103 stops when the normally open contacts of the squeegee up limit switch 136 close. If the contacts do not close, an error message will be displayed.

Drive motor 50 is then driven in reverse for a short duration, causing machine 10 to move in the reverse direction toward the foul line and stop after moving four inches. The squeegee assembly 99 and suction head 98 are then lowered to re-engage the blades 100, 102 with the pin deck 138. Drive motor 50 is then driven in forward to advance the machine forwardly four inches, whereupon it stops to once again cause squeegee assembly 99 to overhang the edge 136 of pin deck 138. Blades 100, 102 snap forwardly to flip off any excess moisture. The squeegee assembly 99 then lifts.

Drive motor 50 now reverses to cause machine 10 to move in the reverse direction toward the foul line at high speed. At the same time vacuum motor 107 is turned off and cleaner pump motor 76 is run in reverse for one second to help reduce the possibility of dripping cleaner out of tip 62 of the cleaner head 58.

As machine 10 travels in reverse, the lane distance sensor 57 counts inches traveled and continuously monitors movement of the machine. If travel is interrupted, an error message will be displayed. As the machine reaches the oil distance, buffer 26 begins to lower and stops in its down position when the normally open contacts of the buffer down switch 21 close. If the contacts do not close, an error message is displayed. If the down switch 21 sticks closed when it should be open, a “brush up” error message will be displayed.

Buffer motor 31 is then energized, causing buffer 26 to begin buffing as the machine continues its travel in reverse. The oil head 28 starts dispensing oil again when the machine reaches the first “reverse load” distance on the lane according to the selected oil pattern program. The machine progressively down-shifts to lower speeds as it continues toward the foul line. When the last reverse load of oil has been applied, the oil head 28 stops and parks. Once the machine reaches the foul line, drive motor 50 is deactivated, causing the machine to stop and await operator attention to move it to the approach of the next lane.

If at any time during its travel up and down the lane machine 10 stops and displays a “LOW BATTERY OR E-STOP PRESSED' warning, this means either battery voltage has dropped below seventeen volts or the emergency stop switch 117 (FIG. 13) has been pressed. In either case, the machine will need to be returned to the foul line and connected to the 120 VAC house power supply for recharging or running on house current using the electrical power supply cord.

The constant voltage regulator 128 plays a significant role in the machine 10 if it is battery-powered (there is no requirement that the machine functions as above described be incorporated into battery-powered machines. However, significant ease-of-use benefits are achieved when they are.) Because the constant voltage regulator 128 is capable of maintaining a constant voltage of twenty-four volts to the key functions of the machine even though the batteries may run down to twenty or twenty-one volts, there is no gradual loss of performance. The machine shows no signs of losing battery power until the voltage drops so low (such as seventeen volts) that the controller 110 simply shuts down and the machine stops and displays the warning. The dispensing head motor 42, oil pump motor 33, buffer motor 31, three-way valve 35, and drive motor 22 all operate from the constant voltage regulator 128.

Zero Turning Radius Machine

The machine 210 as shown in FIGS. 14-29 has many components in common with the machine 10 of FIGS. 1-13. Therefore, much of the foregoing description of the machine 10 applies equally to the zero turning radius machine 210. Only those features of the zero turning radius machine 210 that differ from machine 10 will be described in detail. For the sake of convenience, components of the zero turning radius machine 210 that are the same as those in machine 10 will be identified by the same indicia, or not numbered at all for the sake of clarity.

Broadly speaking, the zero turning radius machine 210 differs from machine 10 in that zero turning radius machine 210 is capable of automatically self-indexing from lane-to-lane so that no operator intervention is required to move machine 210 from one lane to the next. Moreover, machine 210 makes its turns on the approach area behind the foul line about an upright axis located in the center of the machine, thus presenting a zero turning radius. The concept of self-indexing is disclosed in prior U.S. Pat. No. 5,185,901 assigned to the assignee of the present invention, and many of the principles of that prior machine are utilized in machine 210. Accordingly, the '901 patent is hereby incorporated by reference into the present specification.

Machine 210 has two approach drive wheel assemblies 212 and 214 on opposite outboard sides of the machine near the rear. The left approach wheel assembly 212 and its components will sometimes hereinafter be referred to using the descriptor “seven pin”, while the right approach wheel drive assembly 214 and its components will sometimes use the descriptor “ten pin.”

Approach wheel assemblies 212 and 214 each include a pair of fore-and-aft spaced, front and rear approach drive wheels 216 and 218 that are drivingly interconnected by a chain 220. Approach wheels 216, 218 are disposed somewhat lower than lane drive wheels 16, 18 so as to be capable of engaging the surface of the approach while lane drive wheels 16, 18 are not. On the other hand, approach wheels 216, 21 8 are positioned to hang within the gutters of the lane as machine 210 travels up and down the lane, powered by lane drive wheels 16, 18 as they engage the surface of the lane.

With reference to the seven pin approach wheel assembly 212, front approach wheel 216 has a shaft 222 that is driven by a chain 224 operably coupled with the output shaft of a reversible drive motor 226 (FIG. 18) (hereinafter sometimes referred to as the “seven pin drive motor”). Thus, both wheels 216, 218 of seven pin approach assembly 212 receive driving power from motor 226. On the other hand, ten pin approach assembly 214 has its front wheel 216 driven by a shaft 228 that is operably coupled by a chain 230 with the output shaft of main drive motor 22 that drives lane drive wheels 16, 18 (FIG. 19). Thus, both wheels 216, 218 of ten pin approach assembly 214 receive their driving power from lane drive motor 22 and are rotating when lane drive wheels 16, 18 are rotating.

Seven pin approach assembly 212 includes a sprocket 232 on rear wheel 218 that is entrained by a chain 234 which drives a multi-pronged sensor wheel 236. Rotation of sensor wheel 236 is detected by a sensor 238. Similarly, ten pin approach assembly 214 includes a sprocket 240 on rear wheel 218 that is entrained by a chain 242 which drives a multi-pronged sensor wheel 244, the rotation of which is detected by a sensor 246.

The center of gravity of machine 210 is disposed forwardly of front approach wheels 216. Thus, when machine 210 is sitting on the approach, it rocks downwardly by gravity at its front end about front approach wheels 216 and lifts rear approach wheels 218 off the approach (see FIG. 21). This makes rear approach wheels 218 ineffective when machine 210 is on the approach. A pair of caster wheels 248 and 250 are located adjacent the front of the machine in fore-and-aft alignment with front approach wheels 216 so that caster wheels 248, 250 come into engagement with the approach when machine 210 tips forwardly. Consequently when machine 210 is on the approach the only wheels in contact with the approach are caster wheels 248, 250 and front approach wheels 216. This allows front approach wheels 216 to be driven in opposite directions and/or at varying speeds relative to one another so as to turn or steer machine 210 on the approach about an upright axis located midway between front approach wheels 216, the caster wheels 248, 250 merely following along and swiveling as necessary to accommodate the changes in direction.

The front of machine 210 has an upright bumper plate 252 hinged along its top edge to the frame of the machine. A kill switch 254 located behind bumper plate 252 is disposed to be actuated by bumper plate 252 in the event that machine 210 accidentally runs into an object during forward travel. Actuation of kill switch 254 by bumper plate 252 completely shuts down the machine. A pair of anti-friction drag wheels 256, 258 behind bumper plate 252 are disposed to momentarily engage the lane surface as the machine enters and leaves the lane to avoid having the front of the machine scrape or scuff the lane.

The front of machine 210 is also provided with a pair of left and right sensing “whisker” assemblies 260 and 262 that help guide steering and alignment of the machine as it moves from the approach onto the lane. Left whisker assembly 260 and its components will sometimes hereinafter be referred to using a “seven pin” descriptor, while right whisker assembly 262 and its components will sometimes use a “ten pin” descriptor. Each whisker assembly 260, 262 includes an elongated, resilient whisker 264 preferably constructed from a length of coiled spring. Whisker 264 is axially adjustably mounted within a pivot block 266 so that the length of whisker 264 protruding laterally from block 266 can be adjusted. Block 266, in turn, is mounted by a pivot screw 268 for pivoting movement about an upright axis through screw 268. A torsion spring 270 (FIG. 23) wrapped around pivot screw 268 urges the inboard end of block 266 rearwardly toward the actuating lever 272 (FIG. 24) of a switch 274 so that actuating lever 272 is normally depressed. An adjustable screw 276 in the backside of block 266 makes the contacting engagement with lever 272. Switch 274 is electrically connected with the controller 110 to provide input signals thereto for steering machine 210 as hereinafter described.

FIGS. 25-29 are block diagrams illustrating various portions of the control system 108 a of machine 210. Control system 108 a includes, in addition to the electrical components already mentioned above, controller 110 (programmable logic controller Omron model CPM2A), drive motor control 112, an analog expansion module 278 (Omron model MAD01), and control relays CR1, CR2, CR3, CR4, CR5, CR6, CR7, CR8, CR9, CR10, CR11, CR12, CR13, CR14, CR15, and CR1 6. Control system 108 a further includes start switch 116 (FIG. 9), an “on lane” switch 280, right-to-left manual start switch 282, left-to-right manual start switch 284, bottom duster switch 286, cleaning compartment switch 288 (for manually operating duster motors when the duster screen is displayed or manually testing cleaner volume when the oil and cleaner screen is displayed), and an emergency stop switch 117 (FIG. 13).

The controller 110 is equipped with an analog output of 0-5 volts, due to the analog expansion module 278. This voltage, which is sent to the controllers of the various motors of machine 210, can be varied by controller 110 to preset the seven lane speeds and three approach speeds of the machine. For example, if an output of 5 volts is sent to a motor controller, the motor will operate at high speed. On the other hand, if an output of 0 volts is sent to the controller, the motor will coast to a controlled stop. In this application, one analog output controls two motor drives, each receiving the same voltage.

The analog voltage from expansion module 278 is routed though seven pin whisker steering relay CR15 and ten pin whisker steering relay CR16. When these relays are energized, they send a higher analog voltage to their particular steering motor to speed it up, while turning off the analog signal to the other steering motor to slow it down. In this way machine 210 is steered.

The machine 210 must be programmed for a starting lane and ending lane to operate. A starting lane and an ending lane will dictate which direction the machine turns 90 degrees after exiting the lane. The example below will start with lane 1 and end with lane 2 for a left to right travel direction.

When the machine 210 is programmed for its starting and ending lane and then started while sitting on the approach, controller 110 will turn on both seven pin motor forward relay CR11 and ten pin/main motor forward relay CR13. Both ten pin/main motor 22 and seven pin motor 226 will thus turn on and drive the machine forward at a preset slow speed. As the machine moves into the lane, the duster, cleaner pump, squeegee and oil functions start operating at predetermined distances from the starting point on the approach. All are independently adjustable.

As the machine moves forward, the ten pin whisker 264 may strike the foul light if the machine is not perfectly aligned with the lane. The impact will pivot the block 266 away from ten pin whisker switch 274, releasing actuating lever 272 to close the normally closed contacts of ten pin whisker switch 274. This signal turns on input 110 of controller 110, as well as ten pin steering relay CR16.

When input 110 turns on, it causes controller 110 to send a higher analog voltage to the ten pin/main motor control to speed up the ten pin/main motor 22 to a preset turning speed. At the very same moment the analog voltage is turned off to the seven pin motor control to slow down seven pin motor 226. This causes the machine to make a left turn.

When the ten pin whisker 264 returns to its normal position, controller input 110 and ten pin steering relay CR16 will turn off and the two motors 22 and 226 will return to the set speed at which the machine enters the lane.

After making a corrective turn to the left, the machine might now be properly aligned with the lane, in which case it will simply proceed onto the lane. On the other hand, it might be aimed too far to the left such that continued forward movement causes the seven pin whisker 264 to strike the left division rail along the outside of the left gutter. If so, the impact will close the normally closed contacts of the seven pin whisker switch 274. The normally closed contacts of the seven pin whisker switch 274 are wired to controller input 109 such that both input 109 and the coil of seven pin whisker relay CR15 will turn on.

When input 109 turns on, the controller 110 will send a higher analog voltage to the seven pin motor controls to speed up seven pin motor 226 to a preset turning speed. At the very same moment, the analog voltage is turned off to the ten pin/main motor control to slow down ten pin/main motor 22 when the normally closed contacts of seven pin steering relay CR15 open up. This causes the machine to make a right turn.

When the seven pin whisker 264 returns to its normal position, input 109 and seven pin whisker relay CR15 will turn off, and the two motors 22 and 226 will return to the set speed at which the machine enters the lane. The machine might now be aligned with the lane, in which case it proceeds down the lane. If not, it can make additional impacts on the ten pin whisker 264 and seven pin whisker 264 as needed to turn and center the machine.

It should be noted that the machine has an override feature in case the seven pin whisker 264 strikes the lane division for a second time and does not return to its normal position quickly. Such failure to return could be due to the fact that the approach wheels 216 are unable, for some reason, to steer the machine away from the division. In a typical such instance, the machine is fully in the lane but is not able to roll the lane distance wheels 53. To overcome this problem, a timer in the system counts down when the whisker is actuated and switches the machine from approach drive functions to lane drive functions after the elapsed time, causing the machine to move on down the lane.

The machine is programmed to self-adjust when it travels long or short to the next lane so that the over or under travel will not occur the next time the machine is used. The first whisker contact will indicate what adjustment to make, and only that first contact results in an adjustment. All subsequent contacts for each lane will be ignored. There is never an adjustment made on the very first lane. Each adjustment has a magnitude of 0.310 inches.

Assuming the machine is now properly aligned, it continues to move forward onto the lane. When the machine sits on the lane, the approach wheels 216, 218 are disposed within the gutters and are no longer in contact with the floor. Consequently, the lane drive wheels 16, 18 take over. The lane distance wheels 53 also now come into contact with the lane and begin to roll from the forward motion of the machine. When lane distance wheels 53 make one-half of a revolution, the on lane switch 280 will close its normally open contacts and turn on input 000. At that moment the controller 110 will switch from approach drive functions to lane drive functions and the seven pin approach drive motor 226 will turn off to conserve power. The machine will now continue down the lane and return in the same manner as described with respect to machine 10 of FIGS. 1-13.

As the machine approaches the foul line during its return, the return travel distance counters controlled by the lane distance sensor 57 will reach their limit and turn on the seven pin approach drive motor 226 and enable a “stop on approach” counter. (This is also when the machine counts the number of lanes run so the machine will know when to stop operating). The lane distance sensor 57 is part of the reset function for the stop on approach counter and will not allow it to count down until the lane distance sensor 57 stops sending reset pulses. This is so the machine knows exactly where the lane ends and the approach begins.

The machine will then drive onto the approach using all six drive wheels 16, 18, 216, and 218 and stop at the predetermined location behind the foul line far enough away as to not come in contact with the foul lights when turning. Seven pin motor reverse relay CR12 and ten pin/main motor reverse relay CR14 will turn off to stop the machine. Once the machine is fully on the approach, it tips downwardly by gravity at the front about front approach wheels 216 until castor wheels 248, 250 engage the floor. This lifts rear approach wheels 218 slightly off the approach so that the machine is being driven solely by front approach wheels 216 at this time. Of course, main drive wheels 16, 18 are also above the approach and ineffective.

After the machine stops on the approach, there will be a 0.5 second time delay. When the delay is up, the controller 110 will turn on seven pin forward motor relay CR11 and ten pin/main motor reverse relay CR14 to turn the machine 90 degrees in a clockwise rotation which will point the machine in the direction of lane 2. The axis of turning of the machine is located midway between front approach wheels 216 so the machine has a zero turning radius.

The controller 110 then turns on seven pin motor forward relay CR11 and ten pin/main motor forward relay CR13 to drive the machine to the next lane, using the front approach wheels 216. When the machine reaches the next lane, relays CR11 and CR13 turn off to stop the machine. The machine will have a 0.5 second time delay after stopping.

When the delay is up, the controller 110 will turn on seven pin motor reverse relay CR12 and ten pin/main motor forward relay CR13 to turn the machine 90 degrees in a counter-clockwise rotation, which will point the machine facing down lane 2. At this very moment when the machine stops, the controller 110 will reset all functions in its program. After a 0.5 second delay, the machine will begin moving forward to start the entire sequence all over again.

When the machine completes the last lane, it will exit the lane stop on the approach and turn 90 degrees and stop to allow easy access to the cleaning compartment. The machine has a speed decelerate function for all of the stopping functions on the approach. When the machine is 40 counts or less from stopping, the controller 110 will send a slower speed analog signal to the motors 22 and 226 to allow the machine to come to a smooth stop and not a sudden jerky stop. This is so the machine will not tend to be abusive to the drive train when stopping.

In a preferred embodiment, machine 210 is also provided with a pair of free-wheeling bumper wheels 290 and 292 located near the rear of the machine on opposite sides thereof. Bumper wheels 290, 292 are rotatable about upright axes and are positioned a short distance outboard and rearwardly of the rear approach wheels 218. Bumper wheels 290, 292 are thus disposed to engage opposite outside edges of the gutters and kick the rear end of the machine around as necessary to center the machine as it leaves the approach and enters the lane.

The inventor(s) hereby state(s) his/their intent to rely on the Doctrine of Equivalents to determine and assess the reasonably fair scope of his/their invention as pertains to any apparatus not materially departing from but outside the literal scope of the invention as set out in the following claims. 

1. In a lane maintenance machine that is operable to travel up and down successive generally parallel, elongated bowling lanes performing a maintenance operation on each lane and to index between the lanes on a common approach that spans the lanes behind foul lines at one end of the lanes, the improvement comprising: a set of approach drive wheels for propelling the machine while the machine is on the approach; and control mechanism operably coupled with the approach drive wheels in a manner to cause the approach drive wheels to propel the machine on the approach away from the foul line of one lane, turn the machine on the approach until the machine generally faces the next lane, propel the machine transversely on the approach to the next lane, turn the machine on the approach until the machine is lined up with the next lane, and propel the machine on the approach toward the foul line of the next lane for movement down the lane.
 2. In a lane maintenance machine as claimed in claim 1, said approach drive wheels being disposed to hang in gutters on opposite sides of each lane as the machine travels up and down the lane.
 3. In a lane maintenance machine as claimed in claim 2, further comprising lane drive wheels disposed to engage the surface of the lane when the machine is disposed thereon for propelling the machine up and down the lane, said approach drive wheels projecting downwardly beyond the lane drive wheels for maintaining the lane drive wheels disengaged from the approach and the approach drive wheels engaged with the approach when the machine is on the approach.
 4. In lane maintenance machine as claimed in claim 3, said approach drive wheels including a left approach drive wheel and a right approach drive wheel spaced laterally from one another, said control mechanism being operable to drive said left and right approach drive wheels at relatively different speeds and in mutually opposite directions for turning the machine about an upright axis located between said left and right approach drive wheels.
 5. In a lane maintenance machine as claimed in claim 4, further comprising at least one free-swiveling caster wheel disposed to assist the approach drive wheels in supporting the machine when the machine is on the approach.
 6. In a lane maintenance machine as claimed in claim 4, said control mechanism including spaced apart left and right sensors disposed to detect engagement of the machine with an obstruction and operable to provide an output in response to such detection for driving the left and right approach wheels accordingly.
 7. In a lane maintenance machine as claimed in claim 6, each of said sensors including an elongated element projecting outwardly from the machine and mounted for operating movement upon engagement with an obstruction, said operating movement of the element producing an electrical output signal, said control mechanism further including a controller responsive to an electrical output signal from a sensor to operate the approach wheels in a manner to steer the machine.
 8. In a lane maintenance machine as claimed in claim 4, said control mechanism being operable to render the machine self-indexing from lane-to-lane on the approach, said control mechanism including a controller programmed to respond to inputs regarding distance traveled on the approach to operate the approach drive wheels.
 9. In a lane maintenance machine as claimed in claim 1, said control mechanism being operable to render the machine self-indexing from lane-to-lane on the approach, said control mechanism including a controller programmed to respond to inputs regarding distance traveled on the approach to operate the approach drive wheels,
 10. In a lane maintenance machine as claimed in claim 9, said approach drive wheels including a left approach drive wheel and a right approach drive wheel spaced laterally from one another, said control mechanism being operable to drive said left and right approach drive wheels at relatively different speeds and in mutually opposite directions for turning the machine about an upright axis located between said left and right approach drive wheels.
 11. In a lane maintenance machine as claimed in claim 1, said approach drive wheels including a left approach drive wheel and a right approach drive wheel spaced laterally from one another, said control mechanism being operable to drive said left and right approach drive wheels at relatively different speeds and in mutually opposite directions for turning the machine about an upright axis located between said left and right approach drive wheels.
 12. In a lane maintenance machine as claimed in claim 1, said machine being battery-operated.
 13. In a lane maintenance machine, the improvement comprising: a pair of rotatable, axially spaced apart approach drive wheels for propelling the machine while the machine is on an approach behind the foul lines of a set of bowling lanes; and control mechanism operably coupled with said approach drive wheels in a manner for driving the approach drive wheels at relatively different speeds for turning the machine on the approach.
 14. In a lane maintenance machine as claimed in claim 13, said control mechanism being operable to drive the approach drive wheels in mutually opposite directions for turning the machine about an upright axis located between the approach drive wheels.
 15. In lane maintenance machine as claimed in claim 13, said control mechanism including a programmable controller responsive to inputs regarding distances traveled on the approach to operate the approach drive wheels.
 16. In a lane maintenance machine as claimed in claim 15, further comprising lane drive wheels disposed to engage the surface of the lane when the machine is disposed thereon for propelling the machine up and down the lane, said approach drive wheels being disposed to hang in gutters on opposite sides of each lane as the machine travels up and down the lane, said approach drive wheels projecting downwardly beyond the lane drive wheels for maintaining the lane drive wheels disengaged from the approach and the approach drive wheels engaged with the approach when the machine is on the approach.
 17. In a lane maintenance machine as claimed in claim 16, said machine being battery-operated.
 18. In a lane maintenance machine as claimed in claim 13, said control mechanism including spaced apart left and right sensors disposed to detect engagement of the machine with an obstruction and operable to provide an output in response to such detection for driving the approach wheels accordingly.
 19. In a lane maintenance machine as claimed in claim 18, each of said sensors including an elongated element projecting outwardly from the machine and mounted for operating movement upon engagement with an obstruction, said operating movement of the element producing an electrical output signal, said control mechanism further including a controller responsive to an electrical output signal from a sensor to operate the approach wheels in a manner to steer the machine.
 20. A self-propelled, self-steering machine adapted for traveling along a supporting surface, said machine comprising: a mobile chassis; drive wheels supporting said chassis for movement along a supporting surface; left and right steering sensors mounted on the chassis in position for detecting the presence of an obstruction; and control mechanism operably coupled with said drive wheels and responsive to said sensors for driving the drive wheels at the same speed to propel the machine in a straight line path of travel when no obstruction is detected by the sensors and at different speeds relative to one another to turn the machine away from an obstruction when an obstruction is detected by a sensor.
 21. A machine as claimed in claim 20, said drive wheels comprising a pair of left and right, mutually spaced apart drive wheels, said control mechanism being operable to drive the drive wheels in mutually opposite directions for turning the machine about an upright axis located between said left and right drive wheels.
 22. A machine as claimed in claim 21, said control mechanism including a controller programmed to respond to inputs regarding distance traveled on the surface to operate the drive wheels.
 23. A machine as claimed in claim 20, each of said sensors including an elongated element projecting outwardly from the chassis and mounted for operating movement upon engagement with an obstruction, said operating movement of the element producing an electrical output signal, said control mechanism further including a controller responsive to an electrical output signal from a sensor to operate the drive wheels in a manner to steer the machine.
 24. A machine as claimed in claim 20, said machine being battery-operated. 